1. Field of the Invention
The invention relates to a calibration method and calibration system for a robot and, more particularly, to a calibration method and calibration system for a robot having a redundancy.
2. Description of Related Art
A calibration method for mechanism parameters, or the like, of a robot is known as a method described in Japanese Patent Application Publication No. 8-27241 (JP 8-27241 A), Japanese Patent Application Publication No. 2001-50741 (JP 2001-50741 A), or the like. In JP 8-27241 A, a robot is calibrated by a method of collectively calibrating a hand camera and the robot at the same time.
In JP 2001-50741 A, the distal end of a three-dimensional measuring device is coupled to the distal end of an arm of a robot, the position and attitude of the distal end portion of the arm of the robot are measured, and a plurality of teach points are measured while changing the position and attitude of the robot. By so doing, mechanism parameters of the robot are obtained, and calibration is performed.
Japanese Patent Publication No. 4-45842 describes a method of changing the attitude of a robot distal end in a state where the robot distal end is engaged with a displacement detector and then performing calibration on the basis of data of joint angles of joints and data of the displacement detector.
JP 8-27241 A to Japanese Patent Publication No. 4-45842 require a hand camera, a three-dimensional measuring device or a displacement detector, so cost increases.